Evidence for the existence of nonplanar peptide units will be searched for and obtained - for example from accurate crystal structure data from x-ray and neutron diffraction; using NMR studies on model compounds embedded in a liquid crystal medium; from spectroscopic data available in the literature and from investigations to be made on model compounds. The consequences of the new role proposed for hydroxyproline in the collagen structure will be worked out. For example, the structure of the polymer (Gly-Pro-Hyp) sub n will be worked out from theory and the effect of hypro in the collagen structure and the resultant stabilization will be studied. In continuation of the NMR studies, (a) the conformation of diketopiperazines and the effect of side chain backbone interactions would be studied in suitable examples, (b) the structure of other cyclic peptides will be investigated, (c) studies will be made on the Beta-structure occurring in various polypeptides, both by NMR and ORD methods. The advantages coming out of the use of the dihedral angle for representing out-of-plane displacements will be studied with special reference to infrared spectroscopy.